eygle.com   eygle.com
eygle.com eygle
eygle.com  
 

« Oracle 18.3 版本参数比较12.2 看新特性优化诊断增强 | Blog首页 | 2018 Oracle数据库技术大会 - ACOUG在现场 »

Oracle 18.3 和 12.2 版本初始化参数缺省值的改变列表

从 Oracle Database 12.2 到 Oracle 18.3 ,有很多初始化参数的缺省值发生了变化,我整理了一个列表供大家参考。

这其中有些参数和硬件配置有关,但是绝大多数就是因为版本变化做出的改变。尤其是参数值的 True 和 False 的改变。

比如 _use_single_log_writer 的缺省值变成了 TRUE,意味着缺省将禁用自适应 LGWR 的特性。

KSPPINM 		       NEWVALUE 		      OLDVALUE			     KSPPDESC
------------------------------ ------------------------------ ------------------------------ ------------------------------------------------------------
_spin_count		       1			      2000			     Amount to spin waiting for a latch
_super_shared_conversion_threshold 300			      1280			     conversion threshold limit for supershared mode


_num_longop_child_latches      1			      8 			     number of child latches for long op array
_kill_session_dump	       FALSE			      TRUE			     Process dump on kill session immediate
_session_allocation_latches    1			      8 			     one latch per group of sessions
_disable_highres_ticks	       TRUE			      FALSE			     disable high-res tick counter
_enqueue_sync_retry_attempts   15			      3 			     max number of times the bg process to retry synchronous enqu
											     eue open if it failed because master could not allocate memo
											     ry

_enable_shared_pool_durations  TRUE			      FALSE			     temporary to disable/enable kgh policy
_kse_snap_ring_size	       0			      100			     ring buffer to debug internal error 17090
_ksi_clientlocks_enabled       TRUE			      FALSE			     if TRUE, DLM-clients can provide the lock memory
_instant_file_create	       FALSE			      TRUE			     enable instant file creation on sparse media
_ksipc_service_mask	       1			      0 			     KSIPC Service Mask
_proc_grp_enabled	       3			      FALSE			     proc-group enabled
_ksrma_enabled		       off			      OFF			     turn ksrma off, make it automatic, or turn on CMI or KSMSQ p
											     rovider. Default is off

_hang_resolution_promote_proce TRUE			      FALSE			     Hang Management hang resolution promote process termination
ss_termination

_lm_singleton_pdb_opt	       TRUE			      FALSE			     RAC PDB singleton optimization
_lm_rm_object_bypass	       TRUE			      FALSE			     enable read-mostly object bypass for HARIM
_reconfiguration_opt_level     13			      0 			     reconfiguration optimization level
_dlm_stats_collect_mode        4			      0 			     DLM statistics collection mode
_lm_comm_rcv_msg_history_slots 50			      0 			     GES communication receive message history slots
_reliable_block_sends	       TRUE			      FALSE			     if TRUE, no side channel on reliable interconnect
_memory_broker_shrink_heaps    15			      0 			     memory broker allow policy to shrink shared pool
_dbwr_nowrite_assert_interval  7200			      0 			     dbwriter assert interval after no write seconds
_db_block_vlm_check	       FALSE			      TRUE			     check for mapping leaks (debugging only)
_db_cache_miss_check_les       FALSE			      TRUE			     check LEs after cache miss
_db_cache_mman_latch_check     FALSE			      TRUE			     check for wait latch get under MMAN ops in kcb
_db_block_chunkify_ncmbr       FALSE			      TRUE			     chunkify noncontig multi block reads
_db_cache_wait_debug	       0			      1 			     trace new kslwaits
_db_block_iterations_for_rm    2000			      20			     number of blocks to reduce every iteration for RM
_db_dump_from_disk_and_efc     0			      2 			     dump contents from disk and efc
_assert_encrypted_tablespace_blocks TRUE			      FALSE	             if TRUE, assert encrypted tablespace blocks must be encrypted

_high_intrinsic_scn_growth_alert 1440			      60			     high intrinsic SCN growth rate alert time in minutes

compatible		       18.0.0			      12.2.0.0.0		     Database will be completely compatible with this software ve
											     rsion

_num_rlslaves		       2			      16			     number of rl slaves to clear orls
_use_single_log_writer	       TRUE			      ADAPTIVE			     Use a single process for redo log writing
_max_pending_scn_bcasts        8			      9 			     maximum number of pending SCN broadcasts
_gc_trace_freelist_empty       FALSE			      TRUE			     if TRUE, dump a trace when we run out of lock elements
_auto_export_preplugin_backup  TRUE			      FALSE			     auto export pre-plugin backup
_time_based_rcv_ckpt_target    180			      0 			     time-based incremental recovery checkpoint target in sec
_time_based_rcv_hdr_update_int 180			      0 			     time-based incremental recovery file header update interval
erval											     in sec

_nologging_sendbuf_ratio       90			      99			     Nologging standby: outstanding send buffer ratio
_nologging_sdcl_append_wait    200			      100			     Nologging standby append sdcl wait time
_shadow_lost_write_found       118			      22			     Specify shadow lost write error handling

_imtxn_table_enable TRUE FALSE is In-Memory Txn Table cache enabled
_compression_compatibility 18.0.0 12.2.0.0.0 Compression compatibility _dbg_scan 0 2048 generic scan debug _inmemory_subcusize 512 0 In-memory subCU size _inmemory_fsdw_schedlrtm 1 10 in-memory faststart defer write scheduler cycle (sec) _inmemory_repopulate_disable 2 FALSE disable In-memory repopulate _inmemory_repopulate_flags 2 0 In-memory repopulate decision flags _inmemory_dynamic_scans AUTO DISABLE Enable IM Dynamic Scans _imado_optimize_period 0 20 IM-store optimize period for AIM (in minutes) _kql_clientlocks_enabled 15 1 clients allocating DLM memory _pdb_service_on_root_listener FALSE TRUE pdb services on CDB ROOT listeners _cursor_db_buffers_pinned 76 2 additional number of buffers a cursor can pin at once
_qesma_mvob_lru_sz 25 0 size of MVOB LRU list for QESMA session cache _qesma_bo_lru_sz 25 0 size of base object LRU list for QESMA session cache optimizer_features_enable 18.1.0 12.2.0.1 optimizer plan compatibility parameter audit_trail DB NONE enable system auditing _optimizer_undo_cost_change 18.1.0 12.2.0.1 optimizer undo cost change parallel_threads_per_cpu 1 2 number of parallel execution threads per CPU _parallel_adaptive_max_users 4 2 maximum number of users running with default DOP _qa_lrg_type 0 1 Oracle internal parameter to specify QA lrg type _bloom_folding_min 0 128 bloom filter folding size lower bound (in KB) _smm_isort_cap 102400 0 maximum work area for insertion sort(v1) _sqlmon_max_plan 20 160 Maximum number of plans entry that can be monitored. Default s to 20 per CPU parallel_servers_target 20 64 instance target in terms of number of parallel servers _px_chunklist_count_ratio 32 8 ratio of the number of chunk lists to the default DOP per in stance _emon_outbound_connect_timeout 7200000 30000 timeout for completing connection set up to clients _emon_send_timeout 7200000 10000 send timeout after which the client is unregistered _aq_pt_processes 10 15 Partition background processes _asm_disable_proact_client_cle FALSE TRUE disable proactive client cleanup anup _asm_disable_patch_compat FALSE TRUE disable DG patch compatibility checks _asm_allow_prepare_split TRUE FALSE Allow database prepare and split in non-appliance mode target_pdbs 1 2 Parameter is a hint to adjust certain attributes of the CDB max_pdbs 254 4098 max number of pdbs allowed in CDB or Application ROOT _cdb_disable_pdb_limit FALSE TRUE CDB Compatible _cdb_special_old_xplan TRUE FALSE display old-style plan for CDB special fixed table _upgrade_optim TRUE FALSE Upgrade optimization enabled _upgrade_capture_noops TRUE FALSE do not skip capturing noops during upgrade _enable_containers_subquery TRUE FALSE enable transformation to containers() sub query

供大家参考了。


历史上的今天...
    >> 2010-08-02文章:
    >> 2006-08-02文章:
           黑色星期三 本站公告
    >> 2005-08-02文章:
           小美人鱼,我来啦

By eygle on 2018-08-02 08:56 | Comments (0) | Oracle12c/11g | 3296 |


CopyRight © 2004~2020 云和恩墨,成就未来!, All rights reserved.
数据恢复·紧急救援·性能优化 云和恩墨 24x7 热线电话:400-600-8755 业务咨询:010-59007017-7040 or 7037 业务合作: marketing@enmotech.com